Driving mechanism for sewing machines



A. T. MACE DRlvING MECHANISM FOR SEWING MACHINES F11ed Oct. 16, 1919 2 sheets-Sheet 1 Biggi@ A. 1'. MACE- DRIVING MCHANISM FOR SEWING MACHINES 2 sheets-sheet 2 vFilm oct. 16, 1919 A./77 laf/77W iii/ a4 `and driving the Patented Apr. 3, 1923.

UNITED STATES ARTHUR T. MACE, OF CLEVELAND,

OHIO, .ASSIGNOR T THE DOMESTIC ELECTRIC COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO'.

DRIVING MECHANISM FOR SEWING MACHINES.

Application filed October 16, 1919. Serial No. 331,283.

To whom it may concern:

Be 1t known that I, ARTHUR T. MACE residing at Cleveland, in the county of Cuyahoga and State of Ohio, have invented a certain new and useful Improvement in Driving Mechanisms for Sewing Machines, of which the following is a full, clear, and exact description, reference ybeing had to the accompanying drawings.

This invention relates to improvements in motor driven sewing machines, and has particular reference to a mechanism, including 'a-motor, for incorporation in the heads of sewing machines, for operatively connecting upper or needle. bar actuating means and the lower or shuttle actuating means. f

The essential objects of this invention include a novel method of mounting a motor within the usual standard sewing machine head, and the arrangement of simple eilicient gearing and connections for driving the upper and lower shafts actuating the needle and shuttle respectively.'

ore specific 'objects are the arrangement vof mechanism capable of being cheaply manufactured, very durable in likely to get out of order.

An essential point in the commercial use of such an invention is the avoiding of any necessity of increasing the size or altering the shape of the sewing machine heads in which the motors are to be mounted.

Iy invention is hereinafter more fully deuse and not .scribed and is illustrated in the accompany-` ing drawings The essential characteristics are summarized in the claims.

In the drawings: Fig. 1 is a. front elevation of the head of a sewing machine embodying my invention, a portion of the head being shown in central vertical section; Fig. 2 is a plan of the speed reduction means which I employ between the armature and drive shafts; and Fig. 3 is a horizontal section through the head showing the arrangement of the drive shaft adjacent to the motor.

I have illustrated my invention associated with the usual bed plate and standard l1 rising therefrom. 12 designates the usual arm extending horizontally from the upper end of the standard over and parallel to the bed plate 10. Extending longitudinally through the arm 12 and journaledtherein in any suitable manner, is shown the usual needle bar operating shaft 13, carrying the hand wheel 14. Below the bed plate l0 there -is journaled in suitable bracketsas at 16 a shaft 17 by which the shuttle of the machine is actuated. y

The standard casting used in nearly all `modern sewing machines is substantially as shown in the drawings, the upright portion or standard 11 being hollow. In accordance with the purpose of this invention I mount in the standard 11 an electric motor 20, comprising the usual armature 22 having a shaft 21 and field magnets 24 with coils 25. This motor is of a construction commonly used and is selected with View to its adaptability to the purpose of the present invention, the stator being laminated and formed by a series of punchings suitably mounted between the end frame -members 50 and 51 carrying the bearings for the armature shaft. In, the making of these punchings,

Vto,economize on metal and for other pur poses of value kin the design of the motor, each lamination, that is, each punching, is cut away leaving segmentlike recesses 26. Thus a verticalspace is provided at each side of the motor through one of which spaces I may conveniently pass a vertical sha-ft.

As shown in the drawings, I have mounted a shaft in bearings 27, preferably formed integral with the end brackets 50 and 51 of the motor frame, the shaft passing through the recess 26 at the side of the standard toward the ncedle This shaft is held against vertical movement by any suitable means, such, for example, as collars 28 on the shaft, fitted against the bearings 27 as shown. The

needle bar and shuttle actuating shafts 13 and 17 preferably have rigidly mounted thereon bevel gears 31 and 32, respectively, which are driven from corresponding gears 33 and 34 on the ends of the shaft 30.

The drive shaft 30 is itself driven through suitable speed reduction means from the armature shaft 21. I have illustrated a preferred means which consists of an endless belt passing over sheaves 37 and 38, on the armature and drive shafts respectively, and over guide pulleys 39 positioned therebetween. 'The small sheave 37 is secured to the lower end of the armature shaft 21, while the relatively large sheave 38 is rigid with the bevel gear 34`on the lower end of the drive shaft 30.

To enable the flexible member 35 to coopcrate with the sheaves 37 and 3S on the parallel armature and drive shafts. 1 have provided guide pulleys 3S) therefor. suitably supported and tensioned. as by springs 40. within the base beneath the bed pla-tc 1l). Line wires may be brought to the motor either through the side of the standard or from beneath, and its speed may be controlled by the usual rheostat.

lt has been heretofore proposed to mount a motor in the upright portion of sewing machine heads but very pronounced difficulties are encountered in the effort to secure a motor small enough to titinto the standard head and yet powerful enough to operate a machine successfully and capable of running at a sufliciently slow speed while delivering the required power. wing to the limitations of motor design and the limitations of the standard sewing machine heads. this desired result has not to my knowledge been successfully accomplished in any such manner as to answer the commercial requirements for a. successful machine. By the use of the mechanism above described and the selection of a motor of the particular form shown. l have been able to get ample power. even though the motor is necessarilyv a high-speed motor. am able to reduce this speed and yet. drive the upper and lower shafts very positively and at synchronous speed. which is an ab solute requirement of sewing machine operation; in other words, the present invention resides in the, provision of a. driving mechanism capable of use with well-known high speed small motors. whereby l may reduce the speed and yet positively connect the upper and lower shafts and drive them at synchronous speed.

To accomplish these results and avoid thesey difficulties it is essential todirectly connect the upper and lower shafts and yet provide a motor having an outside field diameter as large, as will fit into the standard of the head. Positioning such motor in the head naturally interposcs an obstacle to direct connection of the upper and lower shafts, which I have overcome by the present in- Vention. and in such a manner that I may use a simple and effective speed reduction device at one end only of the armature shaft.

By the arrangement of the reduction means between the armature and drive. shafts. the speed of the drive shaft 3() will be reduced from that of the armature shaft an amount, inverse-ly proportional `to the size of the sheaves 37 and 38 as will be well understood, and the shafts 13 and 17 actuated in synchronism at such a speed as is required for the successful operation of the machine.

claim:

l. lin a sewing machine., a motor mounted witlziin the head thereof, and a draft approximately parallel to, but eccentric of the armature shaft of the motor and connected therewith. a needle bar operating mechanism. shuttle operating mechanism. said eccentrically disposed shaft being geared directlyT to the needle bar operating mechanism and shuttle operating mechanismto drive the. same.

2. 1n a sewing machine head. a hollow upright standard therefor. a motor arranged within said standard. actuating mechanism extending from each end of said standard. a drive shaft mounted in the standard and eccentric to the motor shaft and parallel therewith. said drive shaft being connected to said motor and geared to said actuating mechanism.

3. 1n a sewing machine head. a hollow standard therefor'. a motor arranged within said standard. a shuttle actuating member arranged beneath the bed plate of said machine. a needle bar actuating member within the horizontal arm of the machine.. rand adrive shaft eccentric to said motor and flexibly connected thereto and geared to said actuating members.

4. ln a sewing mahcine head. an electric motor mounted within the hollow standard thereof, a drive shaft within said standard spaced from and extending parallel to the armature shaft thereof and connected` therewith. and gearing means connecting said drive shaft with the needle bar and shuttle actuating members of said machine.

5. ln a motor driven sewing machine` the combination with a. base and horizontal arms for housing the shuttle and needle bar actu ating shafts. and having an interconnecting hollow7 standard. an electric motor mounted within said standard. and ygearing means comprising a shaft'eccentric to the motor connecting said motor with said shuttle and needle bar actuating shafts. y

G. ln a motor driven sewing machine, the combination with shuttle and needle bar actuating means. a hollow standard between said means. an electric motor vertically mounted within said standard. a vertically mounted drive shaft extending through said motor at one side of its armature shaft, speed reduction means connecting said motor with said drive shaft. and gearing between said drive shaft and said shuttle and needle bar actuating means.

7. ln a sewing machine. the combination of housing members for a needle bar and shuttle operating mechanism., a hollow approximately cylindrical standard connecting said members, a motor mounted within said standard of a size sufficient to contact substantially with the walls thereof. a drive shaft mounted eccentric of the motor shaft and extending through and recessed in the field magnet of said motor adjacent the interior wall of said standard and connected retenue to said operating mechanism and to the armature of said motor.

` 8. In asewing machine, a motor mounted in the hollow head thereof,said motor having a vertical armature shaft and a field magnet with a recess adjacent its periphery extending parallel to the armature shaft, and a drive shaft mounted eccentric of the motor shaft in the recess and connected with the armature of said motor and the operating mechanism of said machine through speed reduction means.

9. In a sewing machine, a motor mounted within the head thereof, and means connected with said motor and arranged eccentric of the motor shaft,said means being geared to the operating mechanism of the machine, the field of ,said motor being recessed to accommodate said means.

10. In a motor driven sewing machine, the combination of substantially parallel needle bar and shuttle actuating members suitably housed, a hollow standard extending between said members, an electric motor mounted therein, `a drive shaft geared to said needle bar and shuttle actuating means,

mounted in said standard parallel with and exteriorly of the shaft of the motor, and

speed reduction means between said motor and drive shafts comprising unequal sized sheaves connected by an endless exible member.,

l1. In a sewing machine having a plurality of actuating shafts within suitable housing members, and a hollow standard interconnecting,- said members, a drive shaft therefor, an electric motor occupying substantially the entire space within said standard, the motor being eccentrically recessed to permit the passage therethrough of said aarnnn r. nace. 

